[CI/Build][Docker] Add centralized version manifest for Docker builds (#31492)

Signed-off-by: Mritunjay Sharma <mritunjay.sharma@chainguard.dev>

tools/generate_versions_json.py

@@ -0,0 +1,139 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+"""
+Generate docker/versions.json from Dockerfile ARG defaults.
+
+This script parses the Dockerfile and extracts ARG defaults to create
+a bake-native versions.json file that can be used directly with:
+    docker buildx bake -f docker/docker-bake.hcl -f docker/versions.json
+
+Usage:
+    python tools/generate_versions_json.py [--check]
+
+Options:
+    --check    Verify versions.json matches Dockerfile (for CI validation)
+
+Requirements:
+    pip install dockerfile-parse
+"""
+
+import json
+import sys
+from pathlib import Path
+
+from dockerfile_parse import DockerfileParser
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+DOCKERFILE = REPO_ROOT / "docker" / "Dockerfile"
+VERSIONS_JSON = REPO_ROOT / "docker" / "versions.json"
+
+# Map Dockerfile ARG names (lowercase) to bake variable names (uppercase)
+# This matches docker-bake.hcl variable naming convention
+BAKE_VAR_NAMES = {
+    "torch_cuda_arch_list": "TORCH_CUDA_ARCH_LIST",
+    "max_jobs": "MAX_JOBS",
+    "nvcc_threads": "NVCC_THREADS",
+}
+
+
+def parse_dockerfile_args(dockerfile_path: Path) -> dict[str, str]:
+    """Extract all ARG defaults from Dockerfile using dockerfile-parse."""
+    parser = DockerfileParser(path=str(dockerfile_path))
+
+    # Extract ARGs from structure (more reliable for multi-stage Dockerfiles)
+    args = {}
+    for item in parser.structure:
+        if item["instruction"] != "ARG":
+            continue
+
+        value = item["value"]
+        if "=" not in value:
+            continue
+
+        # Parse ARG NAME=value (handle quotes)
+        name, _, default = value.partition("=")
+        name = name.strip()
+
+        if name in args:
+            # Keep first occurrence
+            continue
+
+        # Strip surrounding quotes if present
+        default = default.strip()
+        if (default.startswith('"') and default.endswith('"')) or (
+            default.startswith("'") and default.endswith("'")
+        ):
+            default = default[1:-1]
+
+        if default:
+            args[name] = default
+
+    # Resolve variable interpolation (e.g., ${CUDA_VERSION} -> 12.9.1)
+    resolved = {}
+    for name, value in args.items():
+        if "${" in value:
+            # Substitute ${VAR} references with their values
+            for ref_name, ref_value in args.items():
+                value = value.replace(f"${{{ref_name}}}", ref_value)
+        # Skip if still has unresolved references (no default available)
+        if "${" not in value:
+            resolved[name] = value
+
+    return resolved
+
+
+def generate_bake_native_json(args: dict[str, str]) -> dict:
+    """Generate bake-native JSON structure."""
+    variables = {}
+    for name, value in args.items():
+        # Use uppercase bake variable name if mapped, otherwise keep as-is
+        bake_name = BAKE_VAR_NAMES.get(name, name)
+        variables[bake_name] = {"default": value}
+
+    return {
+        "_comment": (
+            "Auto-generated from Dockerfile ARGs. "
+            "Do not edit manually. Run: python tools/generate_versions_json.py"
+        ),
+        "variable": variables,
+    }
+
+
+def main():
+    check_mode = "--check" in sys.argv
+
+    # Parse Dockerfile
+    args = parse_dockerfile_args(DOCKERFILE)
+
+    # Generate bake-native JSON
+    data = generate_bake_native_json(args)
+    new_content = json.dumps(data, indent=2) + "\n"
+
+    if check_mode:
+        # Verify existing file matches
+        if not VERSIONS_JSON.exists():
+            print(f"ERROR: {VERSIONS_JSON} does not exist")
+            sys.exit(1)
+
+        existing_content = VERSIONS_JSON.read_text()
+        if existing_content != new_content:
+            print("ERROR: docker/versions.json is out of sync with Dockerfile")
+            print("Run: python tools/generate_versions_json.py")
+            sys.exit(1)
+
+        print("✅ docker/versions.json is in sync with Dockerfile")
+        sys.exit(0)
+
+    # Write versions.json
+    VERSIONS_JSON.write_text(new_content)
+    print(f"✅ Generated {VERSIONS_JSON}")
+
+    # Print summary
+    print("\nExtracted versions:")
+    for name, value in args.items():
+        print(f"  {name}: {value}")
+
+
+if __name__ == "__main__":
+    main()